In this study, primary tumors obtained from 1,129 patients with colorectal cancer were used to measure the mRNA expression levels of the following genes associated with the effects of standard chemotherapy for colorectal cancer: 5-fluorouracil (5-FU)-related thymidylate synthase (TYMS), dihydropyrimidine dehydrogenase (DPYD) and thymidine phosphorylase (TYMP); folate-related dihydrofolate reductase (DHFR), folylpolyglutamate synthase (FPGS) and gamma-glutamyl hydrolase (GGH); irinotecan-related topoisomerase I (TOP1); oxaliplatin-related excision repair cross-complementing 1 (ERCC1); biologic agent-related vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR).
Reduction in γ-glutamyl hydrolase expression is associated with response to uracil and tegafur/leucovorin chemotherapy in patients with colorectal cancer.
A multivariate logistic regression analysis revealed that high folylpolyglutamate synthase (FPGS) gene expression, low gamma-glutamyl hydrolase (GGH) gene expression and low ATP-binding cassette sub-family C, number 1 (ABCC1) gene expression in CRC tissues were predictive factors for a high reduced folate level after LV administration.
In conclusion, we found no significant evidence that genetic variants in FOLR1, GGH, FPGS and SLC19A1 are associated with the risk of colorectal cancer.
Real-time PCR was used to quantify expression levels of folate-associated genes including the reduced folate carrier (RFC-1), folylpolyglutamate synthase (FPGS), gamma-glutamyl hydrolase (GGH),and thymidylate synthase (TS) in tumor tissue and adjacent mucosa of patients with primary colorectal cancer (n=102).